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• The borrow area contains 21,000 cubic yards of suitable plant growth <br />media after topsoil salvage. Approximately 23,000 cubic yards of soil is <br />required to provide a minimum of 18" of cover. It is estimated that 2,000 <br />cubic yards of the existing cover material can be salvaged and re-used for <br />cover. Therefore, adequate cover material exists in the designated <br />borrow area. See Table 14-7 for borrow area quantity calculation. See <br />Appendix 9-4 for the analysis of soil samples 1 through 4. The location of <br />the soil samples is presented on Exhibit 6C, Volume 5, Tab Section 14. <br />Care must be taken to salvage only the suitable plant growth media from <br />the RSRDA borrow area. Additional soil samples will be obtained and <br />analyzed prior to borrow area use to better define the salvage limits. Soils <br />will be analyzed for pH, salinity, texture and sodium adsorption ratio <br />(SAR). <br />Six inches of topsoil will be salvaged from undisturbed portions of the <br />RSRDA borrow area. It is estimated about one-half of the borrow area <br />has been previously disturbed by light use roads, the upper diversion ditch <br />and a prior borrow project, therefore it will be assumed that an average of <br />three inches of topsoil will be recovered from the entire area. The topsoil <br />will be pushed up around the perimeter of the area. Reclamation of the <br />borrow area will involve grading the borrow area to blend into the <br />surrounding contours and redistribution of the topsoil. The south <br />• diversion ditch will be graded to approximate original contours. <br />Grading of the portal bench after sealing the portals will begin with <br />installation of the french drain shown on Exhibit 6C. The french drain <br />system has three branches. Two of the branches will intercept seepage <br />from the portal seals. The third branch is designed to intercept water from <br />the hillside southwest of the conveyor entry. This third leg extends above <br />the level of the portal entries to intercept seepage along the existing <br />hillside. The next reclamation step involves grading concrete and <br />cinderblock remaining from demolition of the shop-office complex into the <br />portal highwall. Sufficient amounts of dirt will be mixed with this material <br />to eliminate voids and promote stability of the fill. Material will be cut from <br />the west end of the portal bench and dozed into the highwall. Topsoil was <br />not salvaged for this area, therefore the best available material from the <br />cut areas will be used for the final cover. An estimated 3 - 4 soil samples <br />taken while moving dirt in this area should identify the best available <br />material. <br />• 14-7 (Rev. 6/02) <br />